This invention relates in general to microprocessors and in particular, to a single chip dual processor wherein a microcontroller (.mu.C) is combined with a digital signal processor (DSP).
The advantages of digital signal processing over analog signal conditioning are well known. Among these include improved noise sensitivity, reliability, and design and reconfiguration flexibility. Also, the combination of a .mu.C and DSP to perform certain digital servomechanism tasks is not new. In these systems, the .mu.C can act as master to a DSP slave under a command-and-response type protocol, or the .mu.C and DSP can operate as independent coprocessors.
There are two drawbacks, however, with prior configurations. First, the programmer must separately program each processor. This requires writing two different programs in two different instruction sets, and providing for communication between the programs. The two processors can then interact through a command-and-response type protocol, and share data through shared data memory. Second, separate external program memories store program instructions for each processor. This not only adds component costs, but also complicates the implementation.
When combining a .mu.C and DSP on the same chip, these drawbacks become accentuated. Therefore, it is a primary object of the present invention to provide a dual processor system which combines a .mu.C and DSP on a single chip without these disadvantages.